It is known to provide a rocker or oscillating-type cutting device in which the blade is mounted on a parallelogrammatic linkage, i.e. a linkage having two mutually parallel spaced-apart arms articulated to respective members so that one of these members will move more or less parallel to itself as the linkage is rocked to and fro by a respective drive.
In the present application, the reference to a parallelogrammatic linkage is intended to include a classical linkage of this type having two such parallel links or arms which have essentially the same effective lengths, as well as any other linkage or kinematic mechanism capable of generating parallel movement of a member.
With the aid of modern computer-controlled drive and control systems, the parallelogrammatic linkage can be simulated by other mechanisms which are intended to be included within the definition of a parallelogrammatic linkage here.
The workpieces, which are intended to be used according to the invention, can be silicon blocks and like sensitive workpieces from which thin silicon plates or the like must be sliced.
In a prior slicing system utilizing a parallelogrammatic linkage and drive, intended for the cutting of stone, namely German patent 553,031 from 1932, the cutting edge of the tool in side view has an inverted roof ridge shape with a large apex angle so that the cutting edge is almost perfectly straight. The roof-shaped configuration facilitates chip removal in the cutting operation.
In this earlier system, there is a long and continuous line of contact between the cutting edge and the cutting contour. Even at high pressing forces between the cutting blade and the workpiece, because of its extended line contact, the cutting action has only limited efficiency. Nevertheless the efficiency requires optimization of the pressing force and in the conventional device additional control means and systems must be provided for regulating the pressing force.
More modern technology developed especially for silicon and other sensitive workpieces (see reprint from Industriediamanten-Rundschau IDR 23, 1989, Nr. 1, Prof. Dr.-Ing. P. G. Werner, Dipl.-Ing. M. Kenter, Dipl.-Ing. M. Cinar "Stand der Technik und zukunftige Entwicklungsmoglichkeiten beim Trennen von Silicium") has not successfully avoided the drawbacks of this system.